1. Field of the Invention
The present invention relates to an automatic integrated circuit testing system, device and method. More particularly, the present invention relates to an automatic integrated circuit testing system, device and method capable of simulating the final states of a terminal user and conducting a dynamic test.
2. Description of the Related Art
Most people directly or indirectly use a server, workstation, desktop computer, notebook computer, portable computer, personal digital assistant, palm-top computer, pocket personal computer or industrial computer. All these computers are built using integrated circuits (ICs). Before putting all these integrated circuits to work sophisticated testing must be conducted to ensure that all of them are in good working order.
FIG. 1 is a block diagram showing the layout of a conventional personal computer. As shown in FIG. 1, major integrated circuits within a conventional personal computer (100) include a central processing unit (CPU) (110), a system bus controller (112) and an input/output bus controller (114). A memory unit (116) and an advanced graphic port (118) are electrically connected to the system bus controller (112) while a monitor (120) for outputting images is electrically connected to the advanced graphic port (118). A peripheral component interface (PCI) is connected to both the system bus controller (112) and the input/output bus controller (114). An integrated drive electronic (IDE) interface (130), a floppy disk (132), a parallel port (134), a serial port (136) and a universal serial bus (USB) (138) are electrically connected to the input/output bus controller (114). In addition, an audio unit (140) and an Ethernet unit (142) may also be electrically attached to the input/output bus controller (114).
The aforementioned devices including the central processing unit (110), the system bus controller (112), the input/output bus controller (114), the memory unit (116), the graphics accelerator within the advanced graphic port (118), the integrated circuit within the expansion interface of the peripheral component interface (122), the audio chip and the Ethernet chip are all constructed from a variety of integrated circuits (ICs). Since all these integrated circuits are important components for the proper functioning of the computer, the performance of the integrated circuits and their compatibility with each other determines the ultimate performance of a computer.
FIG. 2 is a block diagram showing the steps in a conventional method of testing an integrated circuit. A conventional integrated circuit (202), such as logic IC, undergoes a preliminary testing immediately after wafer fabrication. The wafer is cut into chips and packaged. Thereafter, a final test (204) is conducted before shipment (206). In general, the integrated circuit (202) is placed inside automatic test equipment (ATE). The automatic test equipment connects electrically with various contact points on the integrated circuit (202) through a test socket. A pre-determined functional simulation is carried out to test the integrated circuit (202). Operation of the integrated circuit under the simulation is then judged to be normal or not. A conventional integrated circuit test always uses specified programs to carry out the functional simulation and the final state of the device at the end of the test is used to judge for normality. According to the test results, integrated circuits are sorted into separate bins before delivery. For memory ICs, a burn-in test (210) is conducted after the first stage final test (208). The memory IC needs to undergo a second stage final test (212) before shipment to screen out early failure parts. Both the first stage final test (208) and the second stage final test (212) are carried out using automatic test equipment. On the other hand, the burn-in test (210) is carried out manually or semi-automatically. The integrated circuit is plugged into the socket of a testing board and then placed inside a heating station. The integrated circuit is thermally stressed, voltage stressed or current stressed. Nevertheless, this type of integrated circuit testing only tests the functions of an integrated circuit by program simulation and has no special procedures for simulating the actual operating states of a terminal user. Consequently, there is no guarantee for product stability or circuit compatibility after all the integrated circuits are assembled to form a computer system.
FIG. 3 is a block diagram showing the steps carried out in a conventional integrated circuit module test. To resolve the issue of a conventional integrated circuit test not having any terminal user simulation, an IC module test may be inserted between the final test and delivery. To conduct a conventional IC module test, a module such as an interface or a complete computer system is provided. The integrated circuit (302) is manually plugged into a module or a complete computer system capable of simulating a terminal user's operating environment (in step 304). A testing operation (306) is then carried out. Only the integrated circuits passing the test are delivered (308). Since the test is carried out manually and the assessment of test results is also determined by human observation, productivity is lowered while testing time is increased leading to lower yields and higher production costs. Moreover, test accuracy is often affected by errors in human judgment.
In brief, the aforementioned testing procedures have many drawbacks and insufficiencies that may be grouped together as follows:
1. The conventional integrated circuit test makes no allowance for the simulation of a user's final states. That means users may still encounter problems such as conflicts with software even if the test result indicates a pass.
2. A single type of device is placed on the testing board of an integrated circuit tester. Problems resulting from an incompatibility between different types of devices are not investigated.
3. The conventional testing method relies heavily on manual operation leading to a lowering of productivity and an increased possibility of possible human errors.
4. The conventional integrated circuit module testing method after integrated circuit assembly, also known as the module stage, has no provision for varying the operating temperature of a particular device. Hence, the simulation cannot test some actual states of operation.
5. The quality of the integrated circuit is judged according to the final integrated circuit states. Hence, some dynamic errors cannot be determined. For example, such phenomenon as video shaking, discoloring display, ghost shadows or white block in a graphics accelerator cannot be detected. Alternatively, if some software programs executing inside the integrated circuit may bring about a system crash, there is no way for a conventional testing method to discover this problem.